sampling via turntable

i am having trouble sampling through my turntable... i have an ion profile usb turntable with rca cables, but no ground wire and the signal is horrible, the volume is maxed out, and im not able to control the volume, hince no sample. i used a friend's that has the ground wire and the signal came in perfect no issues... im assuming this is because of the ground wire not being there??? just need someone to confirm that for me if you can... also i tried sampling via the 1/4' inputs in the back... it works but not very good... any suggestions???

Yes I believe so....

If your turntable has a built in pre amp and no ground wire, then you should be able to plug the turntable RCAs into the turntable inputs on the back of the MPC and then make sure you press the botton on the top front of the MPC next to the record in volume knob, the "GAIN High/Low" button. Make sure you are in low mode.....

check this video @ 0:43

http://www.youtube.com/watch?feature=pl ... qjYY#t=43s

I'll assume that you are using MPC-4000, as you posted on MPC-4000 section.
DJ A # is right, make sure that your ION turntable is connected to line-in, NOT "phono" on MPC-4000. ION turntable has only line-out (that's why you don't see ground wire), as it has phono preamp build-in. Judging from your description, most likely you've connected wrong way.

If it still does not sound good, then the culprit here is your ION Profile USB turntable. I've seen one of those and I can tell you that you won't get good result with the turntable.

Since you have MPC-4000, you can connect regular record player without preamp build-in, and I'm pretty sure that build-in preamp in the ION turntables are not good (understated.) I was going to suggest to use phono output, connect to phono input on MPC-4000, but ION Profile turnable does not have phono output!
My suggestion is get rid of ION turntable, and look for a used turntable that requires phono preamp. It doesn't have to be expensive turntable.